Means for regulating stroke of fluid-pressure apparatus



Oct. 21, 1952 T R 2,614,537

MEANS FOR REGULATING STROKE OF FLUID-PRESSURE APPARATUS Filed June 28,1950 2 SHEETS-SHEET l INVENTOR. JOHN H. STARR ATTORNEYS MGR GD m mm 1 vw mm Q g a v wt mm m nu \M wm. /JM m .h m 6R a m Q. 3 k. mm W E Q av Nmm a R mm mm mm. m .0 m m R \v N 6R a Q TROKE OF FLUID-PRESSUREAPPARATUS ZSHEETS-SHEET 2 Oct. 21, 1952 J. H., STARR MEANSFOR-REGULATING s Filed June 28, 1950 ATTORNEYS INVENTOR. JOHN H STARRVIA I/IIIIIIIIIIIIIIII I, 1

Figure 7 shows schematically and in section a representative type ofmain control valve for the power lift unit 3. The valve box 4 isprovided with a vertical valve cylinder I within which the valve IOI iscarred for vertical reciprocation. The fluid-pressure circuit includes ahigh-pressure passage I02 in communication at one end with the valvecylinder I00 and in communication at its other with a source of fluidpressure, such as a pump I03. The pump is associated with a suitablereservoir illustrated schematically at I04. Opposite ends of the valvecylinder I00 are in communication respectively with branch passages Iand I00 which provide exhaust branches communicating with a main exhaustpassage IIII terminating in the reservoir I04.

The control lever 5 for operating the valve IN is connected to arockshaft I08 which is journaled in the housing and which has keyedthereto a rockable arm I09. A The arm is connected by a link IIO to theupper end of the main control valve IOI, so that rocking of therockshaft I 08 in one direction or the other will result in verticalshifting of the valve. The rocksh-aft I 08 also has fixed thereto aplate I I I in which is provided a notch I I2. In the neutral positionof the parts, as shown, the notch H2 is engaged by a roller I I3 formingpart of a spring-pressed looking means designated generally by thenumeral H4. When the rockshaft I08 is rocked by the lever 5, the resultis that the means II4 will be depressed and the roller II3 Will ride onone or the other of a pair of fiat portions H5 011 the plate III.Opposite end portions of the plat-e respectively adjacent to the flatportions II5 are provided as lug portions II6, either of which, incooperation with the spring-pressed means II3-I I4, presents increasedresistance to movement of the lever 5 as such portion approaches theroller H3. This provision is made for indicating to the operator the endof slow-speed operation and the beginning of high-speed operation ineither direction. The notch I I2 determines the neutral position of thecontrol valve.

In this respect, it should be noted that the control valve IOI and itsassociation with the remainder of the circuit is of the type providingboth high-speed and low-speed operation for the motor or unit 8. Themanner in which these results are accomplished appears below. For thepresent, it will suffice to note that the operator may move the controllever in either direction to shift the valve IIII in either direction toan extent measured by departure of the roller II3 from the notch I I2and engagement by the roller II3 of one or the other of the lug portionsIIS, depending upon the direction in which the rockshaft I03 is rocked.

The means for automatically returning the valve IIII to the neutralposition shown in Figure '7 includes a second plate II'I fixed to therockshaft I08. This plate is provided at its left hand end with anarcuate portion I I8 which terminates in a pair of cut-oil portions II9.In the neutral positions of the parts, and during ope-ration thereofwithin a certain range, the arcuate portion H8 is in constant engagementwith a roller I provided on one arm of a pivoted bell crank I2I. Thisbell crank is pivoted at I22 on a portion of the housing 4. The otherarm of the bell crank is associated with pressure-relief means includinga vertical rod I23 which extends downwardly in a bore I24 in the housing4. The bore I24 intersects the horizontal portion of the main exhaust orlow-pressure passage I01. The lower end of the rod I23 is headed andcarries thereon a washer I25 between which and the upper portion of thehousing in which the bore I24 terminates is disposed a compressionspring I28. The action of this spring is such as to maintain theengagement of the roller I20 with the armate portion IIB on the plateIII. The extent of the are I I 8 is so proportioned with respect to thecomponents of the plate III that the roller I20 does not depart from thearc as long as rocking of the rocksh-aft, I08 is confined to a range inwhich the roller II3 does not pass either of the lug portions IIB. Inshort, the roller I20 remains in engagement with the arcuate portion H8when the valve mechanism is in its neutral position or when it has beenshifted to either of its slow-speed positions. I

Thehousing I is provided with a passage or bore I28 which is coaxialwith the bore I24 and which intersects both the exhaust passage I IIIand'the lower horizontal portion of the highpressure passage I02. At itslower end, the bore I23 is provided with a valve seat I29 on which isseated a valve I30 which normally" closes the passage or bore againstthe entrance of fluid from the high-pressure passage I02. coiledcompression spring I3I' seats against the valve I30 and against anannular shoulder I32 provided in the bore I28. Above the shoulder I32,the bore I28 caries a valve bodyI33 which normally rests on the shoulderI32 and which has a reduced portion I34 apertured at I35 incommunication with an axial passage or bore I36.

This axial passage communicates with the lower 35 portion of the boreI28.

The spring I3 I is suificiently strong to hold the valve I30 closedexcept against an abnormal or excess rise in pressure in the system.During normal operation of the system, the parts occupy the positionsillustrated in Figure 7. Hence, there is no interaction between thevalve body I33 and the spring-pressed rod I23 for the bell crankIZI.

As previously stated, as long as the rockshaft I08 is rocked duringslow-speed operation of the system, the roller I20 remains in engagementwith the arcuate portion IIB on the plate III. However, should thecontrol lever 5 be moved to its maximum position in either direction,thus increasing the angle of rocking of the rockshaft I08, the rollerI20 will depart from the arc II8 and will engage one or the other of thenotches or cut-oh portions H9. This action results in temporarily andyieldably locking the rockshaft I08 in one or the other of thehigh-speed positions, inasmuch as the spring-loaded rod I23, bell crankI2I, and roller I20 provide a releasable tripping mechanism. Theoperator may,

of course, overcome the action of this tripping mechanism and mayrestore the control lever to its neutral or to either of its other orslowspeed operating positions.

The importance of the present invention is emphasized when-used withmechanism of the fluid-pressure system accomplishes the desiredresult,the control lever will be automatically returned to neutral. In priorknown systems,

A fairly heavy incorporated in the hose line 6. As best shown in Figure5, the valve body 3| has an axial bore 3P at one end of which is a valveseat 31 which is normally open but which may be closed by alongitudinally shiftable plug 38. The valve plug 38 is supported in thevalve chamber 39 in the casing 3| by any suitable means providing forfree movement, such as pins or lugs Aland 42. The plug 38 is preventedfrom turning about its longitudinal axis by means of a screw pin 43, theinner end 44 of which extends into a longitudinally extending groove 45formed on one side of the valve plug 38. The laterally outer face 4? ofthe valve plug 38 is flat and has a groove 48 therein extending normalto the axis of the valve. The groove 48 receives a lug 49'which isformed on the inner end of a valve operating shaft that extendsoutwardly through one side of the valve body 3|, being sealed by asuitable packing 52. The lug 49 is eccentric with respect tothe shaft5|. Rotating the shaft 5| in one direction or the other will shift thevalve plug 38 longitudinally to move the latter toward or away from thevalve seat 31. The packing '52 is compressed by a packing gland 53 ofusual construction. The shaft 5| extends outwardly and at its outer endreceives an arm 55, the central hub section 55 of which is lockedadjustably to the shaft by a socket screw 51 or othersuitable means. Aton side, the hub section 55 is provided with a notch 6| into which aball 62 may extend. A ring member 63 surrounds the hub section 55 andhas a through opening 65 formed therein. An operating arm 66 is carriedby or formed on the ring 63, and surrounding the ring 63 is a secondring or co1lar-69 carrying a pin H.

A spring 72 is connected at one end to the pin and at the other end tothe arm 55, as indicated at 13 in Figures 2 and 4. The outer ring 69 isformed with a ball receiving recess or notch'l5, and the ball 62,together with the through opening 65 and the notches 6| and 15, are soproportioned that the ball may lie either in the opening 65 and notch 75or in the opening 85 and notch 6|, as shown respectively in Figures 4and 2. On its side opposite the arms 55 and 65 the ring 69 carries a pin11 which bears against an extended portion '18 of the valve body 3|. Thepin Tl in bearing against the valve casing 3| prevents clockwisemovement of the ring 69 beyond that shown in Figure 6 (counterclockwisemovement beyond that shown in Figure 2). Since the spring 12 is anchoredat H to the outer ring 69 the spring 12 is'effective to hold the arm 55in the position shown in Figure 2, urging the arm 55 in a clockwisedirection (Figure 2) which acts through the pin 49 (Figure 5) to holdthe valve 38 in its open position, thereby permitting a free flow offluid through the hose line 6 in either direction.

In order to provide a stop against which the spring I2 may act inholding the valve 38 in its open position, a plate 91, preferably formedintegral with the collar 56, is cut out at 98 to accommodate movement ofthe pin 11 on the collar 69, one edge 99 of the cut out 98 beingengageable with the adjacent portion of the valve casing extension 18(Figure 6) and thus stopping the clockwise movement of the valve arm 55under the influence of the spring 72 and holding the valve 38 in itsopen position as the arm 66 is returned from the position of Figure 4 tothat of Figure 2.

According to the present invention, the valve 38 is momentarily closedby movement of the arm 65 in a counterclockwise direction ,(Figure' 2),and this is accomplished in the following manner. A bracket 8| is fixedto the outer end of the piston rod |3 and is apertured to receive theouter end of a control rod 82, preferably secured to the bracket 8| in aselected position by suitable means such as a pair of of lock nuts orthe like. The inner end of the control rod 82 is supported for fore andaft movement in a bracket 83 that is formed on or secured to theextended portion 18 of the valve body 3|. bracket 83 has a curvedsection 84 forming a saddle to receive the control rod 82. The member 83thus disposes the control rod 82 close to the arm 66, as best shown inFigure 3. The control rod 82 is provided with a lug 8'5 thereon. The lug85 is so constructed and arranged that when the piston 2 is forcedinwardly of the cylinder H, as by operating the tractor power lift unit3 to force fluid through the hose 6 and valve 38 to the outer end of thecylinder fluid from the inner end of the cylinder flowing through thehose line 1 and back to the valve box 4, the control rod 82 is movedtoward the right (Figure 1). Movement of the rod 82 to the right(Figure 1) causes the lug 85 to approach the arm 66 and during thefurther inward movement of the piston l2 and the corresponding furthermovement of the rod 82, the lug 85 swings the notchfil, whereuponfurther movement of the arm 66 swings the spring biased arm 55 in acounterclockwise direction. Since the arm 55 is secured to the shaft,the valve 38 is shifted to the left, or toward'its closed position,imposing a restriction or stoppage in the line 6 to an extent suflicientto cause such rise in fluid pressure as will actuate the relief ValveI33, following which the valve |8| is returned to neutral. At the sametime, as the two members 53 and 55 have moved together in acounterclockwise direction, the ball 62 drops into the notch at aboutthe-point where the lug starts to pass under the arm 68. When the ball82 drops into the notch 15, it clears the notch 6|, whereupon.

the tensioned spring 12 now acts to return the arm 55-and the valve 38tothe'pcsition shown in Figure 2, which opens the valve 38 (Figure 5), thearm 66, however, remaining in the position of Figure 4. Thus, when thepiston structure l2,

l3 reaches a given position, depending upon the adjustment of the rod 82in the bracket 8|, the control valve 38 is momentarily closed. Thisclosing of the valve 38 occupies only a short space of time but issufficient to cause the valve mechanism 3 on the tractor to trip,locking the hydraulic unit 8 against further movement. However, sincethe valve 38 opens almost immediately, all that it is necessary to do tofurther retract the piston is to direct more fluid under pressurethrough the hose line 6. g

A second lug is adjustably fixed on the control rod 82 in such aposition that when the .piston rod I3 is again moved towards itsoutermost position (Figure l) the lug 95 engages the arm 66 and moves itfrom its position shown in Fig"- ure 4 to the position shown inFigure 2.This The a closure and adapted when connected thereto to shift saidclosure into a closed position, means for disconnecting said arm meansfrom said closure at the point where the latter substantially reachesits closed position, means movable by relative movement of said motormembers in one direction for shifting said arm means to cause saidclosure to be closed when the motor members are moved relatively in saidone direction to a given point in their range of movement, and meansoperated byrelative movement of the motor members in the other directionfor shifting said arm means into a position in which it is reconnectedwith said valve closure.

5. In an agricultural implement of the type having a part adapted to beadjusted by power, the combination of a power unit including valvemechanism automatically returnable to a neutral position upon theoccurrence of excessive pressure in the system, a double-actinghydraulic power unit including a fluid chamber and a motor membermovable therein, a pair of fluid conduits leading from said valvemechanism to opposite ends of said chamber to conduct'fluid to and fromopposite sides of said motor member, a control valve unit in one of saidconduits and including a valve and a valve seat, movement of the motormember in one direction being accompanied by a flow of fluid throughsaid one conduit in a direction past said valve toward and through saidseat, and means actuated by movement of said motor member in said onedirection to shift said valve toward said valve seat in the direction ofsaid fluid flow, whereby as said valve is moved to a position closelyapproaching said valve seat the resulting throttling action on the fluidflow establishes a pressure differential on opposite sides of the valvewhich results in a completion of the movement of the valve to its closedposition and thereby eflecting the return to neutral of said power unitvalve mechanism.

6. In an agricultural machine including a part to be shifted by power,the combination of a source of hydraulic power including valve mechanismautomatically returnable to a neutral position upon the occurrence of anabnormal pressure in the system, a hydraulic motor having relativelymovable members connected with said part, a conduit extending betweensaid unit and said valve mechanism and accommodating a flow of fluid inone direction between said unit and said valve mechanism when the motormembers are moved relatively, means including a valve and valve seatinterposed in said conduit and arranged so that said valve is movable insaid one direction with said fluid flow toward said seat, and valveoperating means connected with said valve and one motor member forcausing movement of the latter to move said valve in said one directiontoward said seat to a point sufficiently close to said seat so as tothrottle the fluid flow and create sufficient pressure differential onopposite sides of said seat to complete the closing of said valveagainst said seat independent of further movement of said one motormember and thereby to increase the pressure in said system to returnsaid valve mechanism to its neutral position.

'7. For an implement of the type having a part adjustable in differentdirections by fluid-pressure apparatus including a fluid motor havingrelatively movable parts operative to adjust the implement partselectively in any of the aforesaid directions, a source of fluidpressure, a fluid-pressure-transmitting circuit including thefluidpressure source and the motor and a manually operated main controlvalve for regulating the flow of fluid pressure between the source andthe motor, the improvement comprising: second valve means in thecircuit, separate from the main valve and effective to open the circuitso that the main control valve may regulate the circuit for thetransmission of fluid pressure at a predetermined rate between thesource and the motor to effect operation of the motor for adjusting theimplement part in one direction, or to positively close the circuit,apart from manual regulation of the circuit by the main control valve,for completely discontinuing transmission of fluid pressure to themotor; means engageable by one of the aforesaid parts and in controllingassociation with the second valve means and operative automatically inresponse to a predetermined extent of said one-direction operation ofthe motor to effect closing of the second valve, and means energized byclosing movement of the second valve and automatically effectiveimmediately subsequent to closing of the second valve for automaticallyreopening the second valve to condition the circuit for subsequentmanual regula tion by the main control valve to transmit fluid to themotor at the aforesaid rate for subsequent operation of the motor toadjust said part further in said one direction and beyond the aforesaidpredetermined extent.

8. For an implement of the type having a part adjustable in a certaindirectionby fluid-pressure apparatus including a fluid motor havingrelatively movable parts operable to adjust the implement partselectively in said direction, a source of fluidpressure, afluid-pressure-transmitting circuit including the fluid-pressure sourceand the motor and a main control valve for regulating the flow of fluidpressure between the source and the motor, the improvement comprising:second valve means in the circuit, separate from the main valve andeffective to establish a first condition of circuit-control, in whichthe circuit transmits fluid pressure between the source and the motor toeffect operation of the motor for adjusting the implement part in saiddirection, or a second condition of circuit-control for discontinuingoperation of the motor, actuating means engageable by one of theaforesaid parts and in controlling association with the second valvemeans and operative automatically in response to a predetermined extentof said one-direction operation of the motor to effect the aforesaidsecond circuit-control condition of the second valve; and meansconnected with the circuit and effective subsequent to the occurrence ofsaid second circuit-control condition of the second valve means forautomatically conditioning the circuit for continued operation of themotor to adjust said part further in said direction beyond the aforesaidpredetermined. extent, and said actuating means including cooperatingelements having provision forv overrunning after actuation of the secondvalve so that continued operation of the motor may be had withoutaffecting said second valve.

9. In an agricultural implement of thetype having a part adapted to beadjusted by power, a fluid-pressure system comprising: the combinationof a power unit including valve mechanism automatically returnable froma manually set activating position to a neutral position upon theoccurrence of excess pressure in the system, a fluid-pressure motorhaving means for connection with the implement tool means and having afluid-transmitting connection with the power unit, a control valve insaid fluidtransmitting connection and having a first actuating element,means including a second actuating element operated by actuation of saidmotor to a predetermined extent for engagement with the first actuatingelement to close said control valve to an extent sufficient to create acondition resulting in excess pressure in the system and thus to stopthe motor by efiecting the return to neutral of said valve mechanism,releasable means operated by actuation of said motor to saidpredetermined extent to store energy for causing re-opening of saidcontrol valve so that subsequent setting of the valve mechanism in itsactivating position will cause actuation of the motor beyond saidpredetermined extent, and said actuatingelements being separable afterclosing and re-opening of the control valve to accommodate overrunningof one element by the other as the motor is actuated beyond saidpredetermined extent.

10. In an agricultural implement having a part adapted to be adjusted bypower, the combination of a fluid-pressure power unit including valvemechanism for controlling the transmission of fluid under pressure toand from said power unit and including means responsive to an abnormalincrease in pressure for returning the valve mechanism from a manuallyset activating position to a neutral position in which such fiuidtransmission is discontinued, a fluid-pressure motor having motormembers movable relatively through a given range and adapted to beconnected with said implement part for adjusting said part,fluid-transmitting means extending from said motor to said valvemechanism, a valve in said fluid-transmitting means having a fluidflowrestricting phase and biased for change to an open phase accommodatingrelatively free transmission of fluid through said fluid-transmittingmeans, a first actuating element connected to the biased valve and asecond actuating element connected with one of the motor members andcooperative with the first actuating element to change said biased valveto its fluid-flow restricting phase when said motor members moverelatively to agiven position within said range so as to cause saidvalve mechanism of said power unit to be returned to its neutral psition, said first actuating element including a releasable connectionwith said biased valve operative to release said biased valve forsubsequent return to its open phase to provide for subsequent manualsetting of the valve mechanism in its activating position to effectoperation of said motor beyond said given position, and said actuatingelements having provision for the overrunning of one by the'other as themotor is operated beyond said given position.

11. For an implement of the type including a supporting part and animplement part connected thereto for movement with respect thereto in atleast one direction: fluid-pressure apparatus comprising a fluid motorhaving first and sec- 0nd parts provided with means for connectionrespectively to the implement and supporting parts and arranged formovement of one relative to the other in at least one direction to movethe implement part as aforesaid; a source of fluid pressure having highand low sides; a fluidpressure circuit connected to and including thefluid-pressure source and the motor for transmitting fluid pressurebetween the motor and the source; a control valve in the circuitselectively movable to a neutral position to cut out the circuit betweenthe source and the motor or to an active position for establishing thecircuit; pressure-relief means in the circuit operative in response toabnormal fluid pressure in the circuit for by-passing the motor anddiverting the fluid pressure to the low side of the fluidepressuresource; means connected between the pressurerelief means and the controlvalve for returning the control valve from its active position to itsneutral position in response to actuation of said pressure-relief means;means including a second valve in the circuit actuatable from a firstposition conditioning the circuit for the supply of fluid to the motorat normal pressures, to a second position restricting said circuit to anextent sufiicient to cause an excess of pressure therein effective tooperate the pressurerelief means; actuating means operative in responseto a predetermined extent of movement of one motor part relative to theother in said direction for actuating the second valve means from itsfirst position to its second position and hence to effect return of thecontrol valve to neutral via operation of said pressure-relief means;means operative in response to actuation of said second valve means toits second position for conditioning the circuit for the subsequenttransmission of fluid between the motor and said source so thatre-positioning of the control valve to its active position is effective-JOHN H. STARR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,223,792 Muir Dec. 3, 19402,243,364 Trautman May 27, 1941 FOREIGN PATENTS Number Country Date527,171 Great Britain Oct. 3, 1940 327,386 Germany Oct. 11, 1920

